Maurice purchased a coin collection several years ago. Each year he has had the
ID: 2625845 • Letter: M
Question
Maurice purchased a coin collection several years ago. Each year he has had the collection appraised by a reputable coin dealer. Maurice has calculated the yearly percentage gain or loss based on the appraisal, as shown below:
Year 1: 10%
Year 2: 5%
Year 3: 9%
Year 4: -5%
Year 5: 2%
Year 6: -3%
Year 7: 12%
What is the average (mean) return of the coin collection over the seven-year period?
Use the rate of return data provided by Maurice to calculate the geometric mean return. How does this compare to the mean return?
Explanation / Answer
Average rate of return = average of all the values given = (10%+5%+...+12%)/ = 30%/7 = 4.2857%
geometric mean return = (Geometric mean of (1+r%) of all the above values) - 1
= {(1+10%)*(1+5%)*...*(1+12%)}^(1/7) - 1= 4.1057%